Treatment of natural calcium phosphate.



EDGARD CISELET AND CAMILLE DEGUIDE, OF BRUSSELS, BELGIUM.

TREATMENT NATURAL CALCIUM PHOSPHATE.

1 142,008. no Drawing.

To all whom it may concern:

Be it known that we, EDGARD CISELET and CAMILLE Daemon, subjects of the King of the Belgians, residing at .189 Avenue Brugmann and 100 Avenue Lepoutre, Brussels,

Belgium, have invented certain new and useful Improvements in the Treatment of Natural Calcium Phosphate, of which the following is a specification. I

The present invention has for its object to render natural phosphates of lime and the like, in particular poor chalky phosphates, readily assimilable by plants, without having recourse to the use of acids, and

-cium chlorid which may be subsequently eliminated b Washing and recovered, the phosphate 0' lime being deposited in the form of an. amorphous powder which is easily assimilated by the roots of plan-ts.

In comparison with thetreatment'with sulfuric ;acid, this process has great advantages both from the point of view of economy and quality of the product obtained. Thus, as the dissolvent is a soluble salt and can be almost wholly recovered the cost of manufacture is reduced to practically that, necessary for carrying out the manipulations. Furthermore, by the use of a neutral salt, the effect of which does not decrease the richness of the treated phosphate; poor phosphates may be converted intocompara' tively rich fertilizers. being perfectly assimilable by plants, do not possess anyacid character which may have a detrimental efiect onthe said plants. Finally, lime which generally accompanies tricalcic phosphate in natural phosphates, is not'afiectedby a neutral salt as it is by acids so that the fertilizer manufactured in accordance with this invention contains all the lime which was originally contained the treated phosphate:

The process may be Specificationof Letters Patent.

The latter, while carried out in the following manner: The phosphate to be treated which is preferably previously crushed, is mixed with a concentrated solution ofa suitable neutral salt, such as calcium chlorid. The mass is subsequently dried. and then heated to a temperature of about 1000 C. in a' furnace, Under the action of heat the mass melts and the phosphate of lime as well as lime which may be accompanying it, are dissolved in the melted chlorid of calcium. After a certain time, the mass is withdrawn from the furnace, crushed and then subjected to a methodical washing 'in water which dissolves the calcium chlorid. The phosphate of lime which is'insoluble in water and is collected, dried and crushed, is then obtained in the form of an amorphous powder suitable'for being easily assimilated by the roots of plants. Furthermore, the calcium chlorid carried away by the washing water, may be recovered and thereby serve for a fresh treatment.

The given by way of example, will produce good results in practice :-To 100 kilograms of poor chalky phosphate containing 40% of tricalcie phosphate and 47% of carbonate of lime, 49 kilograms of calcium chlorid in solution,'the coefficient of. concentration of which is 50%, are added. After drying, the resultingmass is subjected to the hereinbefore described operations.

,What we claim and desire to secure by Letters Patent of the United vStates is:

1.1 In a process for the pre aration of assimilable. phosphates, dissolving. natural phosphate in melted calcium chlorid and eliminating thecalcium chlorid by washing. 2.?Tna process for the preparation of assimilable phosphates, mixing natural following proportions, which are.

' Patented Jan. 34), T9 17; Application filed February 19, 1914. Serial No. 819,774; I

phosphate'with a concentrated solution of "calcium chlorid,- drying the mixture thus obtained, melting said mixture by the action of heat, submittingthe mass to washing "obtained, crushing said mass, washing the samewith water, collecting and drying the phosphate, and recovering the calcium chlorid carried away by the water.

4. In a process for the preparation of assimilable phosphates, crushing natural -phosphate, mixing about 100 parts by collecting and drying the phosphate, and recovering the calcium chlorid carried away by the water.

In testimony whereof we have aifixed our 5 signatures in presence of two witnesses.

EDGARD CISELET. CAMILLE DEGUIDE.

Witnesses:

ADOLPHE VOGEL, HENRY W. PLUOKER. 

